A conventionally known sensor system that is used with a vehicle to conduct periphery monitoring includes a plurality of ultrasonic sensors and an ECU (that is, a control device), which are connected with one signal line for serial communication.
The above-mentioned sensor system uses a detection operation instruction frame, which is transmitted from the ECU to the ultrasonic sensors, and a response frame, which is transmitted from the ultrasonic sensors to the ECU. The required number of such frames is determined based on the number of ultrasonic sensors. Additionally, the conventional sensor system causes the ECU to transmit the detection operation instruction frames to the ultrasonic sensors, then wait for a waiting time until the ultrasonic sensors terminate their detection operations, and sequentially receive responses from the ultrasonic sensors after the elapse of the waiting time. This causes a problem in which the intervals (hereinafter referred to as the detection intervals) before the next ultrasonic sensor's detection operation are increased.
As such being the case, a technology for addressing the above problem is disclosed, for instance, in Patent Literature 1. This technology incorporates detection operation instructions for a plurality of ultrasonic sensors into one detection operation instruction frame.